Projectable and retractable stitch tongue equipped, zig-zag sewing machine



Dec. 19, 1967 J. E. SHARP 3,358,631

PROJECTABLE AND RETRACTABLE STITCH TONGUE EQUIPPED, ZIG- ZAG SEWING MACHINE Filed June 21, 1965 6 Sheets-Sheet l INVENTOR JAMES E. SHARP BY WM, Qua 3% ,5 M

I ATTORNEYS 1967 J. E. SHARP 3,358,631

PROJECTABLE AND RETRACTABLE STITCH TONGUE EQUIPPBD, ZIG-ZAG SEWING MACHINE Flled June 21, 1965 6 Sheets-Sheet 2 INVENTOR I JAMES E. SHARP BY v. MW PWIL 2% A M ATTORNEYS Dec. 19, 1967 J E. SHARP 3,358,631

PROJECTABLE AND RETRACTABLE STITCH TONGUE EQUIPPED, ZIG- ZAG SEWING MACHINE Filed June 21, 1965 6 Sheets-Sheet 5 JAMES E. SHARP ATTORNEYS v INVENTOR Dec. 19, 1967 J. E. SHARP 3,358,631

PROJECTABLE.AND RETRACTABLE STITCH TONGUE EQUIPPED, ZIGZAG SEWING MACHINE 6 Sheets-Sheet 4.

Filed June 21, 1965 JAMES E. SHARP ATTORNEYS J. E. SHARP 3,358,631 CTABLE AND R RACTABLE 5 CH TONGUE QUIPPED, ZI AG SEWING CHINE Dec. 19, 1967 7 6 Sheets-Sheet 5 Filed June 21, 1965 INVENTOR JAMES E. SHARP ATTORNEY;

Dec. 9, 1967 J. E. SHARP 3,358,631

PROJECTABLE AND RETRACTABLE STITCH TONGUE EQUIPPBD ZIG ZAG SEWING MACHINE Flled June 21 1965 6 Sheets-Sheet 6 mm m m Mo v m A M United States Patent M 3 358 631 PROJECTABLE Ami RETRACTABLE STITCH rgr fi un EQUIPPED, ZIG-ZAG SEWING MA- James E. Sharp, Chicago, 11]., assignor to Union Special Machine Company, Chicago, 111., a corporation of Illinois Filed June 21, 1965, Ser. No. 465,314 30 Claims. (Cl. Ill-260) ABSTRACT OF THE DISQLOSURE A sewing machine having a throat plate equipped with a needle hole, a stitch tongue guided in the throat plate and projectable into and retractable from the needle hole under operator control at any time during or after a sewing operation of the machine, stitch forming means including a needle reciprocated for passage through the needle hole alternately at opposite sides thereof to lay stitches across the tongue when the tongue is projected into the needle hole, reversible work feeding means, presser foot means and means for lifting the presser foot to permit reverse feeding of the material, the action of retracting the tongue being accompanied by a reversing of the feed direction and an actuation of the presser foot lifting means, and projection of the tongue being accompanied by a restoration of work feed action to normal forward.

The invention relates generally to sewing machines and more particularly to machines of the two-thread, chain or lock stitch zig-zag sewing type examples of which are shown in US. letters Patent 3,068,818, issued to E. Schoij et al. on Dec. 18, 1962, and 2,792,797 issued to R. A. Hayes et al. on May 21, 1957, and it primarily seeks to provide novel projectable and retractable stitch tongue means.

More particularly the invention provides a novel stitch tongue or stitch finger means disposed within the horizontal confines of the sewing machine throat plate and subject to being projected in the feed line into stitch receiving position preparatory to zig-Zag stitching and which may in like manner be retracted from such effective position at any time before, during or after stitching operation of the machine, always without necessity for a stopping of machine operation during any tongue projecting or retracting action.

Stitch finger use is well known in the art. It is well known that the nature of zig-zag stitching is such that the thread tends to pull the material together in a direction across the line of feed and this causes the material to pucker or balloon upwardly along the stitch line, thereby providing an unslightly, faulty and undesirable seam or ridge. Moreover, any attempt to back stitch or back tack over such seams would provide even more unsightly and undesirable back stitching or back tacking. In an effort to solve this problem, known stationarily or otherwise mounted stitch fingers have been provided, but these have been found only partially successful and practical and have not solved the problems encountered in back stitching or back tacking.

In the employment of known stitch fingers, when zigzag stitching is in progress, the needle or the looper thread is carried by the needle or the complementary stitch forming devices across the stitch finger so that each thread overlay will have a length greater than the spacing of the points at which the laterally vibrated needle enters the material, thereby to provide necessary slackness in the overlying or zig-zag thread. Thus when the material so stitched is moved along by the feeding mechanism in the normal feeding direction, the threads lying across the 3,358,631 Patented Dec. 19, 1967 stitch finger will be caused to slide off the latter, there being a certain slackness in the cross threads, as aforesaid. It is this slackness that provides for the final flat appearance of the seam, since it provides for enough thread to compensate for the relaxation of the thread from its rather tensioned state during the setting of the stitches and which without provision of such slackness would cause the beforementioned unsightly, puckered ridge or scam in the material.

Known stitch finger equipments worked fine in normal or forward sewing, but could not be used where back stitching or back tacking was to be practiced because in such practices back feeding or reverse feeding of the material is absolutely necessary and this cannot be accomplished with a stationary finger projecting between the material and overlying zig-zag stitches, or with movable but improperly positioned stitch fingers which would interfere with the necessary back feeding of the material.

Therefore, it is an object of the present invention to provide a novel form and arrangement of stitch tongue mounted to normally lie with its end extremity projected into a generally triangular needle hole in the sewing machine throat plate so that the reciprocating and laterally vibrated needle can pass down through said hole first to one side and then to the other side of the tongue during the formation of zig-zag stitches, said tongue being retractable from the needle hole at any time at the will of the operator when back stitching or back tacking is to be performed, and without the necessity of stopping of the machine.

Another object of the invention is to provide a stitch tongue which is projectable and retractable in a straight line and in the line of feed in the manner stated and which is slidably supported on or arranged for movement in the sewing machine throat plate with the uppermost surfaces of the throat plate and stitch tongue in coplanar relation.

A further object of the invention is to provide in a sewing machine of the character stated projectable and retractable stitched tongue means, presser foot lifting means, and thread tension releasing means, and cooperative means manually operable to first retract the stitch tongue, and then lift presser foot a predetermined limited amount to permit back stitching or back tacking.

Yet another object of the invention is to provide cooperative manually operable means of the character last stated wherein said means is operable also to release the thread tension, but only after the intended back stitching or back tacking has been completed.

A still further object of the invention is to provide in a projectable and retractable stitch tongue equipped sewing machine of the character stated means operable for feeding material being stitched either in the normal forward direction with the stitch tongue projected, or in reverse direction with the stitch tongue fully retracted.

Still another object of the invention is to provide in a sewing machine of the character stated wherein is provide a reversible material feed and a projectable and retractable stitch tongue, cooperable means for controlling the direction of feed and the projection and retraction of the stitch tongue, retraction of the stitch tongue being accompanied by reversal of the material feed, and restoration of the feed to normal forward being accompanied by projection of the stitch tongue.

Another object of the invention is to provide in appara tus of the character stated spring operable means for projecting to and maintaining the stitch tongue in its normal projected position, and manually operable means for retracting the stitch tongue.

Still another object of the invention is to provide in apparatus of the character stated spring operable means for projecting to and maintaining the stitch tongue in its normal projected position and for arranging the material 3 feed in its normal forward feeding condition, and manually operable means for retracting the stitch tongue and reversing the material feed to its reverse feed condition.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing.

In the drawings:

FIGURE 1 is a vertical longitudinal sectional view through the frame of a zig-zag sewing machine embodying the invention.

FIGURE 2 is a plan view of the base portion of the machine with the cloth plate removed and a portion of the frame and certain parts being shown in horizontal section.

FIGURE 3 is a view partly in elevation and partly in vertical cross section through the machine with the cover plate removed from the head of the frame.

FIGURE 4 is a vertical cross section through the standard of the machine taken on the line 4-4 on FIGURE 1 and looking leftward toward the tension release mechanism to which the feed tongue actuating mechanism is connected.

FIGURE 5 is a detail plan view of the throat plate with the stitch tongue assembled therein.

FIGURE 6 is a plan view of the throat plate per se.

FIGURE 7 is a sectional view of the throat plate along line 7-7 on FIGURE 6.

FIGURE 8 is a sectional View of the throat plate along line 88 on FIGURE 6.

FIGURE 9 is an inverted plan view of the throat plate showing the stitch tongue assembled therein, together with portions of the throat plate support and portions of the stitch tongue actuating mechanism.

FIGURE 10 is a fragmentary plan view of the throat plate support showing the guide groove for receiving the stitch tongue shank.

FIGURE 11 is a front edge view of the plate shown in FIGURE 10.

FIGURE 12 is a perspective view of the stitch tongue.

FIGURE 13 is a detail plan view of the stitch tongue actuating bell crank.

FIGURE 14 is a front edge view of the bell crank of FIGURE 10.

FIGURE 15 is an illustration, in plan view, of the stitch tongue arrangement in the throat plate support in relation to the alternate needle position, looper blade and loop retainer hook.

FIGURE 16 is a fragmentary sectional view illustrating the clamp means for the stitch tongue actuating wire in section.

FIGURE 17 is a fragmentary side elevation illustrating the stitch tongue actuating wire connected to the tensio release actuating crank.

FIGURE 18 is a fragmentary reverse side elevation illustrating the actuating lever for the tension release rock shaft.

FIGURE 19 is a detail view illustrating the presser foot lifter lever bell crank construction.

FIGURE 20 is a perspective view illustrating a reverse feed mechanism incorporated in a chain stitch machine in combination with the stitch tongue feature of the invention.

FIGURES 21 and 22 are fragmentary perspective views of the feeding mechanism of FIGURE 20, portions being broken away.

FIGURE 23 is a plan view of the novel stitch tongue and throat plate associated with the feeding mechanism shown in FIGURE 20.

, FIGURE 24 is a front elevation of the parts shown in FIGURE 23, partially in section.

FIGURE 25 is a side elevation of the parts shown in FIGURE 23.

FIGURE 26 is a perspective view illustrating the feed rocker, the slide element cooperative with the arcuately slotted segment portion of the rocker also being shown beside the latter.

While the invention disclosed herein is applicable to various forms of sewing machines, particularly such as are subject to use in the formation of zig-zag stitching of the chain stitch or lock stitch type identified, among others, by the Federal Specifications Board of the United States as types 304-305-404 and 405, the form of the sewing machine to which the invention disclosed herein FIGURES 1 through 19 is applied will be recognized in the trade as the standard Union Special 53100 zig-zag machine. For greater detail in part description of said machine than is given herein, reference may be had to the Schoij et al. Patent 3,068,818, issued on Dec. 18, 1962, FIGURES 1, 2 and 9 of the drawings in which disclose subject matter corresponding substantially to that shown in the drawing FIGURES 1, 2 and 3 herein. With respect to the FIGURE 4 herein and the known parts there disclosed, reference may be had to the Hayes et al. Patent 2,792,797 for greater descriptive detail than the relatively brief part references .given herein.

FIGURE 2 of the drawings herein shows the invention as installed in said above referred to class 53100 machine. More particularly, the invention is comprised of a throat plate 10 mounted on the throat plate support 11 which is fastened to the machine frame 12 by screws 13. The throat plate is provided with the usual triangular needle hole or slot 14, the stitch tongue groove 15 leading into the needle hole and the various feed dog slots 16 best shown in FIGURES 2, 5 and 7. At its other end, the stitch tongue groove 15 opens into an aperture 17 which, in this particular throat plate, is enlarged forwardly at 18 to accommodate the central forward feed prongs or teeth of the feed dog 19. The aperture 17 is slightly ex tended beyond the front end of the said slots in order to accommodate the stitch tongue base 20.

In FIGURE 2 the stitch tongue 21 is shown as projecting into the triangular needle hole 14, between the alternate needle positions indicated at 22 and 23. This is the normally projected position of the stitch tongue. This stitch tongue 21 is formed with a narrow tongue portion or finger piece 24 extending into the base portion 20, and an offset shank portion 25. The latter is provided with a transversely disposed slot 26 for receiving a mounting screw 27, as best shown in FIGURE 2. The narrow tongue portion, as well as the base portion of the stitch tongue, is slidably arranged in the groov 15 and aperture 17, respectively. The shank portion 25 is disposed below the throat plate, as shown in FIGURE 3 and is slidably arranged in a groove 28 in the throat plate support 11, see FIGURES 1-0 and 11. The guide groove 28 is provided with a hole 29 which is elongated in the line of feed.

The mounting screw 27 extends with its shoulder portion through the slots 26 and 29 and is threaded at its lower end into a receiving tap in th lever arm 30 of the bell crank 31, as will be apparent by reference to FIGURE 3. The bell crank 31 is pivotally mounted at 32 on the undersurface of the throat plate support 11. Connected to the other arm 33 of said bell crank is the end of a steel wire 34, see FIGURES 1 and 9. In order to provide means for adjusting the leverage of the bell crank, its arm 33 is provided with an elongated slot 35 along which the wire mounting screw 36 may be adjusted, then to be secured in order to fix the adjustment. Secured to the undersurface of the throat plate support and adjacent the rear edge of the arm 30 of the bell O crank 31, there is a support bracket 37 serving as a support for one end of the wire guide tube 38, see FIGURES 2 and 9.

It will be observed that if the bell crank 31 is angularly displaced about its pivot 32, the stitch tongue 21 will be retracted correspondingly so that its tapered free end extremity will no longer project into the needle hole, compare FIGURES 2, 5 and 9. A coil spring 39 arranged about the wire 34 between the wire support bracket 37 and the arm 33 of the bell crank 31, urges the bell crank to pivot toward the throat plate so that the stitch tongue will be maintained in its normal projected position in the needle slot (FIGURES 2 and 9) unless the steel wire means 34 is properly acted upon to retract the same to the position illustrated in FIGURE 5. It will also be noted that the support bracket 37, in abutting the bell crank arm 30, serves as a means for fixing the distance the stitch tongue may extend into the needle hole. It will be noted that the mounting holes at 40' in the bracket 37 are somewhat elongated in the line of feed so that the degree of extension of the stitch tongue into the needle hole may be adjusted.

As can be seen by reference to FIGURES 2 and 17, the actuating wire 34 extends through the tube 38 which is arranged along the front side of the machine, terminating in an upwardly bent portion supported by the bracket 41 secured to the vertical standard of the machine, as clearly illustrated in FIGURES 4 and 17 of the drawings. The wire 34 is guided through said tube and protrudes therefrom at both ends. The wire end protruding from the bent portion of the tube 38, best shown in FIGURE 17, is secured to a stud 42 of a crank arm 43 by suitable means, such as a clamp screw 44, a clamp collar 45 and an adaptor screw 46. Said crank arm 43 is fastened to the forward end of a shaft 47 extending through the vertical standard of the machine from the rear to the front thereof. The shaft 47 serves as means to actuate the tension release plate 48. It is to be understood that in this particular arrangement, the stitch tongue retracting mechanism is coupled to the tension release mechanism which, in turn, is coupled to the presser foot lifter mechanism generally designated 49. A more detailed description of the tension release and the presser foot lifter mechanism can be found in the Hayes et al. Patent 2,792,797, and said mechanism includes the actuator plate 50 pivotally supported at 51 on the machine frame and slotted at 52 to receive the pin projecting from the crank 53 carried by the shaft 47 as shown in FIGURES 4 and 18. The

1 plate 50 has an actuator 54 connected at its free end as It is important to note that whenever back stitching or back tacking is intended, the tension release plate 48 will be so adjusted that upon actuating the presser foot lift mechanism, the tension will not be released, that is the wedge portions 57 will not effectively engage between the tension disks 58. The reason for this is that the threads must remain under full control during the back tacking operation. Should the tension be released at this time, the stitch threads would tend to bunch up at the underside of the material and thus spoil the seam.

Referring now to FIGURES 3 and 19, it will be observed that there is provided a torsion spring 59 disposed to be effective in urging the presser foot to a depressed or downward position. This torsion spring contributes, through its influence upon the tension release rock shaft, in the maintenance of the stitch tongue in its forward position in the needle hole, as shown in FIGURE 9. In this particular adaptation of the invention, the previously mentioned spring 39 serves primarily to compensate for a certain motion lost when the steel wire 34 is acted upon by the tension release mechanism.

From the foregoing, it will be apparent that in the machine structure and part arrangement illustrated in FIGURES 1 through 19 the zigzag stitching can proceed in the normal and well known manner with the stitch tongue projected in the manner illustrated in FIGURES 2, 3 and 9, the same being positioned, as best illustrated in FIGURE 2, for having the needle descend alternately at opposite sides of the stitch tongue and lay the zig-zag stitching thereover in a manner for assuring against upward ballooning or puckering of the steam when in normal practice the material is fed forwardly and the overlaid zig-zag stitching is removed olf the free end of the stitch tongue. Whenever it is desired to do any back stitching or back tacking the stitch tongue may be retracted to its position illustrated in FIGURE 5 with slight lifting of the presser foot so that the operator can manually move the material during said back tacking or back stitching, at any time desired.

In FIGURES 20 through 26, there is disclosed an alternative arrangement of the invention wherein provision is made for reverse feeding of the material when there is an intention to practice back tacking or back stitching. As above stated, it was necessary in the previously disclosed machine structure to slightly lift the presser foot during reverse sewing so that the operator could move the material by hand in the reverse direction. The means disclosed herein for providing for the desired reverse feeding of the material in combination with the projectable and retractable stitch tongue features will now be described. As before stated, FIGURES 20 through 26 illustrate the invention in combination with a zig-zag sewing machine including a reverse feed mechanism embodying a feed bar 60 which is given a four-motion movement by means including eccentrics 61 and 62. The feed bar 60 has its rearward end pivotally connected to a rocker 63 which swings freely about a stationary shaft 64. The eccentric 61 cooperates with the strap of the upper end of a pitman 65, the lower end of which is pivotally connected to an arm 66 which extends downwardly and forwardly from the feed bar 64), as best shown in FIGURES 20 and 22. In this arrangement the feed bar 60 has its forward end lifted and lowered during each revolution of the main shaft 67 shown in FIGURE 20. The other eccentric 62 receives a strap at the forward end of a pitman 68, the rearward end of which is pivotally connected with the feed rocker 69 which is mounted on the stationary shaft 64, as shown in FIGURE 20.

The feed rocker 69 is thus given a swinging movement of a fixed magnitude about the stationary shaft 64. A forwardly extending arm 76 of said rocker 69 is pivotally supported on the shaft 64 intermediately of its length and closely adjacent to the segment portion 71 carried at the free forward end thereof, as best shown in FIGURE .26. The segment portion 71 is provided with an arcuate slot 72 extending substantially equal distances above and below the axis of the shaft 64, see FIGURES 22 and 26. In the arcuate slot 72 there is arranged a slide element 73 which is carried at the rearward end of a link connection 74. At its forward end said link connection is pivoted to the downwardly extending arm 66 of the feed bar 60, said feed bar carrying the usual feed dog in the usual and well known manner and cooperative relation with the throat plate. It will thus be seen that, as the feed rocker 69 is swung, the feed bar 60 will be reciprocated longitudinally by means of the link connection 74. The position of the slide element 73 in the arcuate slot 72 determines the extent and direction of the feed. If the slide element 73 is above the central or neutral point in the slot 72, then the material is fed in a forward direction. If the slide element is below said neutral point, then the material is fed in reverse direction.

The slide element 73 is connected through a link 75 to the free end of a lever 76 which is secured to a bar or rocker 77. A second lever 78 is fastened to the opposite end of said bar 77 and pivoted at its upper end to a link 79, which, in turn, is pivoted to an arm 80 fixedly mounted on the reverse feed actuating or control shaft 81 which is disposed along the outside of the base of the machine frame 82. The actuating shaft 31 is connected at its right end with a hand lever 83 and a standard knee press arrangement generally designated 84, as shown in FIGURE 20. This knee press arrangement includes the knee press 85 adjustably mounted on the rocker 86 which is crank and link connected at 87 with the rocker or 7 actuator 88 fixed on the abovementioned actuating shaft as shown in FIGURE 20.

The throat plate 89 and stitch tongue 90 employed in this modified disclosure are of the same construction described earlier in connection with the disclosure in FIGURES 1 through 19, with the exception that the shank of the stitch tongue may or may not be provided with a mounting hole. It will be observed by reference to FIGURES 23 and 25 that in this modified form of the invention, the stitch tongue 90 may be fixedly secured to an actuating bar 91 by screw means, riveting or welding. It is to be understood, of course, that the throat plate 89 somewhat fragmentarily shown in FIGURE 20 is disposed to receive in its slots the material engaging teeth of feed dog means supported on the feeding bar 60 as aforesaid. The actuating bar 91 extends transversely in relation to the reverse feed actuating shaft 81. Ad-.

justably secured to the shaft 81 and cooperating with said actuating bar 91 is a fork member 92 straddling the actuating bar and abutting a pin 93 extending transversely through said actuating bar, as shown in FIGURES 23 and 25. A spring 94 serves as a cushion means to prevent damage to the stitch tongue during the actuation of the reverse feed mechanism.

It may be further observed from FIGURE 20 that the stitch tongue 90 is normally (during forward sewing) maintained projected into the throat plate needle slot by the same spring means that normally maintain the feed mechanism in the forward sewing position. These spring means comprise the torsion spring 95 of the knee press arrangement and a tension spring 96 arranged between the arm 8%) on the shaft 81 and a bracket 97 on the frame 82.

Upon actuation of the reverse feed mechanism, the shaft 81 will be angularly moved in counterclockwise direction as viewed in FIGURE 25. By reason of this, the fork member 92 will act upon the actuating bar 91 through the spring 94 and, in shifting the same in the direction of the operator, will retract the stitch tongue from the needle slot. It is to be understood that this retraction of the stitch tongue 90 will precede actual reverse feeding of material by the hereinabove described reverse feeding mechanism.

It will be readily understood that in the operation of this modified machine structure, the normal forward feeding and zig-zag stitching will be carried on with the parts adjusted in the condition illustrated in FIGURE 20. Whenever it is desired to perform back stitching or back tacking, the knee press or hand control may be manually actuated to bring about a retraction of the stitch tongue from the position illustrated in FIGURE 20 immediately followed by a reversing of the direction of material feed, as previously described.

In the foregoing description there are disclosed alternative machine structures one in which the operator must first slightly lift the presser foot and then manually move the then freed material reversely when back stitching or back tacking is to be performed, and other in which reverse feeding means is provided which makes it possible for an operator to practice back stitching or back tacking without the necessity for first lifting the presser foot, the reverse movement of the material in this instance being effected by the reverse feed means.

In the first described machine structure the stitch tongue retraction effecting devices are connected in cooperative relation with the presser foot lifting means, and in the last described machine structure it is found advantageous to connect the stitch tongue position controlling devices in cooperative relation with the reverse feed control means, as previously described.

While preferred example disclosures of the first and alternative forms of the invention have been disclosed herein it is to be understood that variations in the part structures and arrangements specifically disclosed herein 8 may be varied without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. In a sewing machine, the combination of a throat 7 plate having a needle hole therein, means for feeding material along a feed line generally centered on said needle hole, a stitch tongue guided for movement along said feed line, means for projecting said tongue into and retracting it from said needle hole during a sewing operation of the machine, and stitch forming means including a needle and means for reciprocating the needle for passage through the needle hole and alternately at opposite sides of said feed line thereby to lay stitches across the stitch tongue when said tongue is projected into the needle hole.

2. In a sewing machine, the combination of a throat plate having a needle hole therein, means for feeding material along a feed line generally centered on said needle hole, a stitch tongue guided for movement along the said feed line, means for projecting said tongue into a position at least part way over the length of the needle hole in said feed line and retracting it from said position at any time during or after a sewing operation, and

stitch forming means including a needle and means for reciprocating the needle for passage through the needle hole and alternately at opposite sides of said feed line thereby to lay stiches across the stitch tongue when said tongue is projected into the needle hole.

3. The combination defined in claim 1 wherein said tongue projecting and retracting means includes means remotely operable at the will of and by an operator for bringing about a projection or a retraction of the stitch tongue.

4. The combination defined in claim 2 wherein said tongue projecting and retracting means includes means remotely operable at the will of and by an operator for bringing about a projection or a retraction of the stitch tongue. 7 a

5. The combination defined in claim 1 wherein the stitch tongue is supported and guided on the throat plate and lies Wholly Within the horizontal confines thereof.

6. The combination defined in claim 1 wherein the stitch tongue is supported and guided on the throat plate and lies wholly within the horizontal confines thereof with its uppermost surface in coplanar relation to the uppermost surface of the throat plate.

7. The combination defined in claim 1 wherein said tongue projecting and retracting means includes means operable at the will of an operator for projecting and retracting the stitch tongue and for maintaining said stitch tongue in either of said projected or retracted position during the production of a desired succession of stitches.

8. The combination defined in claim 2 wherein said tongue projecting and retracting means includes means operable at the will of an operator for projecting and retracting the stitch tongue and for maintaining said stitch tongue in either of said projected or retracted position during the production of a desired succession of stitches.

9. The combination defined in claim 2 wherein there are included means operable at the will of an operator for projecting and retracting the stitch tongue, there also being included a presser foot and presser foot lifting means, the stitch tongue being projected in the direction of normal feed along the feed line so that stitches laid across the tongue will slide off the free end of the tongue during normal feeding of the material, and said means operable at the will of the operator to retract the stitch tongue and permit reverse feeding of the material for back stitching also includes devices for actuating the presser foot lifting means and effecting a desired lifting of the presser foot during said back stitching.

10. The combination defined in claim 1 wherein there are included means operable at the will of an operator for projecting and retracting the stitch tongue, there also being included a presser foot and presser foot lifting means, the stitch tongue being projected in the direction of normal feed along the feed line so that stitches laid across the tongue will slide off the free end of the tongue during normal feeding of the material, and said means operable at the will of the operator to retract the stitch tongue and permit reverse feeding of the material for back stitching also includes devices for actuating the presser foot lifting means and effecting a desired lifting of the presser foot during said back stitching.

11. The combination defined in claim 1 wherein there are included means operable at the will of an operator for projecting and retracting the stitch tongue, a presser foot cooperable with the material feeding means, and said means operable at the Will of an operator including a common actuator manually operable by the operator to first retract the stitch tongue and then effect a lifting of the presser foot.

12. The combination defined in claim 2 wherein there are included means operable at the will of an operator for projecting and retracting the stitch tongue, a presser foot cooperable with the material feeding means, and said means operable at the will of an operator including a common actuator manually operable by the operator to first retract the stitch tongue and then effect a lifting of the presser foot.

13. The combination defined in claim 2 wherein the throat plate is mounted on a support and the stitch tongue includes a base and a shank and is supported and guided in part on said support and in part in said throat plate, there also being included means operable at the will of an operator for projecting and retracting the stitch tongue, said last named means including a pivoted bell crank having one arm thereof connected with the stitch tongue shank and its other arm connected with a manually operable retraction wire, and a spring means also engaging said other arm and constantly tending to move the bell crank'to a stitch'tongue projecting position.

14. The combination defined in claim 1 wherein the throat plate is mounted on a support and the stitch tongue includes a base and a shank and is supported and guided in part on said support and in part in said throat plate, there also being included means operable at the will of an operator for projecting and retracting the stitch tongue, said last named means including a pivoted bell crank having one arm thereof connected with the stitch tongue shank and its other arm connected with a manually operable retraction Wire, and a spring means also engaging said other arm and constantly tending to move the bell crank to a stitch tongue projecting position.

15. The combination defined in claim 14 wherein the stitch tongue guided in the throat plate lies wholly within the horizontal confines of the throat plate, and wherein there is included stop means engageable by one arm of the bell crank for limiting the distance of projection of the stitch tongue into the needle hole.

16. The combination defined in claim 14 wherein the stitch tongue guided in the throat plate comprises a narrow free ended finger piece with its base depending from the non-free end portion thereof and merging into the shank which is horizontally disposed and connected with the said one arm of the bell crank, the uppermost surface of said finger piece lying in coplanar relation to the uppermost surface of the throat plate.

17. The combination defined in claim 14 wherein the stitch tongue guided in the throat plate comprises a narrow free ended finger piece with its base depending from the non-free end portion thereof and merging into the shank which is horizontally disposed and connected with the said one arm of the bell crank, the uppermost surface of said finger piece lying in coplanar relation to the uppermost surface of the throat plate, said narrow free ended finger piece being supported and guided in a groove in the throat plate, and said horizontal shank being supported and guided in a slot in the throat plate support.

18. The combination defined in claim 2 wherein there are included means operable at the will of an operator for projecting and retracting the stitch tongue, there also being included a presser foot and presser foot lifting means, the stitch tongue being projected in the direction of normal feed along the feed line so that stitches laid across the tongue will slide off the free end of the tongue during normal feeding of the material, and said means operable at the will of the operator to retract the stitch tongue and permit reverse feeding of the material for back stitching also includes devices for actuating the presser foot lifting means and effecting a desired lifting of the presser foot during said back stitching, and said last named means and devices including a rock shaft having two crank arms thereon, a pivoted bell crank having one arm thereof connected with the stitch tongue and its other arm connected with one end of a retraction Wire, spring means also engaging said other arm and constantly tending to move the bell crank to a stitch tongue projecting position, the other end of said wire being connected to one of said crank arms, and the other of said crank arms being connected with a manual actuator and with said presser foot lifting means.

19. The combination defined in claim 2 wherein there are included means operable at the will of an operator for projecting and retracting the stitch tongue, there also being included a presser foot and presser foot lifting means, the stitch tongue being projected in the direction of normal feed along the feed line so that stitches laid across the tongue will slide off the free end of the tongue during normal feeding of the material, and said means operable at the will of the operator to retract the stitch tongue and permit reverse feeding of the material for back stitching also includes devices for actuating the presser foot lifting means and effecting a desired lifting of the presser foot during said back stitching, and said last named means and devices including a rock shaft having two crank arms thereon, a pivoted bell crank having one arm thereof connected with the stitch tongue and its other arm connected with one end of a retraction wire, spring means also engaging said other arm and constantly tending to move the bell crank to a stitch tongue projecting position, the other end of said Wire being connected to one of said crank arms, and the other of said crank arms being connected with a manual actuator and with said presser foot lifting means, there also being included thread tension release means and means operable by movement of one of said crank arms for bringing about a releasing of the tension only after lifting of the presser foot and completion of intended back stitching.

20. The combination defined in claim 4 wherein there also are included means for effecting a reverse feeding of the material and means operable each time the stitch finger is retracted to bring about an operation of said reverse feed effecting means.

21. The combination defined in claim 4 wherein there also are included means for effecting a reverse feeding of the material and means operable each time the stitch finger is retracted to bring about an operation of said reverse feed effecting means, and operable upon projection of the stitch finger to again restore in action the first mentioned material feeding means to normal forward feeding condition.

22. The combination defined in claim 4 wherein there also are included means for effecting a reverse feeding of the material and means operable each time the stitch finger is retracted and upon completion of said retraction to bring about an operation of said reverse feed effecting means.

23. The combination defined in claim 1 wherein there also are included means for effecting a reverse feeding of the material and means operable each time the stitch finger is retracted to bring about an operation of said re verse feed effecting means.

24. The combination defined in claim 1 wherein there also are included means for efiecting a reverse feeding of the material and means operable each time the stitch finger is retracted to bring about an operation of said reverse feed effecting means, and operable upon projection of the stitch finger to again restore in action the first mentioned material feeding means to normal forward feeding condition.

25. The combination defined in claim 1 wherein there also are included means for effecting a reverse feeding of the material and means operable each time the stitch finger is retracted and upon completion of said retraction to bring about an operation of said reverse feed effecting means, and operable upon projection of the stitch finger to again restore in action the first mentioned material feeding means to normal forward feeding condition.

26. The combination defined in claim 4 wherein the work feeding means is reversible so that the material can be fed forwardly when normal stitching is in progress with the stitch tongue projected and reverse feeding can be effected when back stitching is to be performed with the stitch tongue retracted, means including a manually operable rock shaft and operating connections for selectively conditioning the reversible feed means for forward or reverse feeding, spring means normally urging and holding said rock shaft and operating connections in the forward feed effecting condition, means connecting the rock shaft and the stitch tongue to hold the latter in its projected position when the material feeding means is conditioned for forward feeding and for moving the tongue to its retracted position incidental to the conditioning of the feeding means for reverse feeding, and manually operable devices for controlling the position of the rock shaft.

27. The combination as defined in claim 26 wherein said last named devices include a manually operable lever and a knee press.

28. The combination defined in claim 1 wherein the work feeding means is reversible so that the material can be fed forwardly when normal stitching is in progress with the stitch tongue projected and reverse feeding can be'effected when back stitching is to be performed with the stitch tongue retracted, means including a manually operable rock shaft and operating connections for selectively conditioning the reversible feed means for forward or reverse feeding, spring means normally urging and holding said rock shaft and operating connections in the forward feed effecting condition, means connecting the rock shaft and the stitch tongue to hold the latter in its projected position when the material feeding means is conditioned for forward feeding and for moving the tongue to its retracted position incidental to the conditioning of the feeding means for reverse feeding, and manually operable devices for controlling the position of the rock shaft.

29. The combination as defined in claim 26 wherein the stitch tongue and rock shaft connection includes 'a projecting and retracting thrust member attached to the stitch tongue and a forked crank fixed on the rock shaft and straddling the thrust member, and abutment means carried by the thrust member and opposed at opposite sides to the free end of the forked crank.

30. The combination as defined in claim 26 wherein the stitch tongue and rock shaft connection includes a projecting and retracting thrust member attached to the stitch tongue and a forked crank fixed on the rock shaft and straddling the thrust member, and abutment means carried by the thrust member and opposed at opposite sides to the free end of the forked crank one said abutment means comprising a cross pin and the other a compression spring.

References Cited UNITED STATES PATENTS RICHARD J. SCANLAN, JR., Primary Examiner. 

1. IN A SEWING MACHINE, THE COMBINATION OF A THROAT PLATE HAVING A NEEDLE HOLE THEREIN, MEANS FOR FEEDING MATERIAL ALONG A FEED LINE GENERALLY CENTERED ON SAID NEEDLE HOLE, A STITCH TONGUE GUIDED FOR MOVEMENT ALONG SAID FEED LINE, MEANS FOR PROJECTING SAID TONGUE INTO AND RETRACTING IT FROM SAID NEEDLE HOLE DURING A SEWING OPERATIONG OF THE MACHINE, AND STITCH FORMING MEANS INCLUDING A NEEDLE AND MEANS FOR RECIPROCATING THE NEEDLE FOR PASSAGE THROUGH THE NEEDLE HOLE AND ALTERNATELY AT OPPOSITE SIDES OF SAID FEED LINE THEREBY TO LAY STITCHES ACROSS THE STITCH TONGUE WHEN SAID TONGUE IS PROJECTED INTO THE NEEDLE HOLE. 